Multiple article forming apparatus



Jan. 21, 1964 Filed NOV. 17, 1960 E. B. CLIFFORD 3,118,487

MULTIPLE ARTICLE FORMING APPARATUS 2 Sheets-Sheet 1 MTTUFPNE'LJ/ Jan. 21, 1964 E. B. CLIFFORD MULTIPLE ARTICLE FORMING APPARATUS 2 Sheets-Sheet 2 Filed Nov. 17, 1960 7/ VENTUI? 5.5 ULPU U United States Patent 3,118,487 MULTIPLE ARTKCLE FGRMING APEARATUS Eugene B. Clitford, West Grange, NJ assigner to Western Electric Company, Incorporated, New York, N.Y., a corporation of New York Filed Nov. 17, 196%, Ser. No. 69,897 2 Claims. (Cl. 15325) This invention relates to multiple article forming apparatus, particularly multiple forming punches and dies simultaneously forming articles of like or varied thicknesses.

In the manufacture of contact springs for various electrical units such as relays, switchboard jacks or the like, the springs are punched out of fiat material and then given subsequent forming operations depending upon their positions and functions in the electrical units. Due to the large number of articles of this type, required to satisfy the demand for their use, it is desirable to perform the forming operations as well as the punching operations in multiple tool apparatus. However, in the forming of articles of this type, there is a disturbing problem resulting from the variations in thicknesses of the articles. The articles are intended to be of the same thickness but, in practice, their thickness varies with the variations in the thickness of the initial stock from which the articles were punched. If the forming operation should be the production of like bends in the articles, certain known bends of predetermined angles must be formed under like conditions, that is like or sufficient pressures, to accomplish a set bend in each article, recognizing the fact that the resilient nature of the material will tend to return the bent portion toward its initial position. If the dies of a multiple forming apparatus should be mounted at fixed positions and the punches should be fixed against relative movement in the punch holder during the forming of articles, one of which is thicker than the others, the one article would receive the predete mined maximum pressure but would prevent the other articles from receiving the desired pressure suitable for performing like forming operations. This variation may be from .001 to .004 in thickness but it is sufficient to bring about the undesired result, the unbalancing of pressure of the punches and dies on the articles.

The object of the invention is a multiple forming apparatus wherein uniform pressures may be applied to pairs of tools utilized in forming articles of like or varied thicknesses.

In accordance with the object, the multiple forming apparatus has a plurality of pairs of forming tools such as dies and punches having companion surfaces cooperating to form articles of equal or varied thicknesses by the aid of hydraulic means causing application of equal pressures to like tools of the pairs of tools although movements thereof, toward their companion tools, may be varied by articles of different thicknesses.

More specifically, the hydraulic means is embodied in a punch holder where a chamber with an opening covering the area of the punches has a diaphragm closing the opening of the chamber and positioned to be engaged by the punches. The diaphragm is formed of a non-compressible flexible material and the chamber is filled with a non-compressible fluid so that there may be varied movements of the punches resulting from varied thicknesses of articles being formed to result in uniform pressures on all of the punches to produce like formations in the articles through the aid of the dies.

Other objects and advantages will be apparent from the following detailed description when considered in conjunction with the accompanying drawings wherein:

HQ. 1 is a side elevational view of the apparatus, portions thereof being shown in section;

Patented Jan. 21, 195

FIG. 2 is a horizontal sectional view taken along the line 22 of FIG. 1; and

PEG. 3 is an isometric view of one of the articles illustrating its straight line position prior to forming and the bent position subsequent to forming.

The apparatus includes a base it mounted on a bed ll. of a press. A stationary tool or die holder 12 mounted on the base It and grooved at 14 to receive plurality stationary forming tools such as forming dies 15 mounted at spaced positions. The dies 15 are identical and have forming surfaces 16 disposed in alignment with each other. The articles, in the present instance, are presumed to be identical but may differ in form and, not intentionally, but actually, vary in thickness.

The article, illustrated at 17 in FIG. 3, has apertures 18 therein for use in mounting in its respective electrical unit. Each die is provided with a hopper Ztl for a stack of articles 17 which are to be fed singly to their respective dies. The feeding means includes a single unit, such as an a r cylinder 21, having a piston rod 22 fixed to a member 23 to which a feeding element 2. for each hopper is attached. The feeding elements are supported for sliding movement in guide-like grooves 25 in the die holder 12 to move the articles singly from their hoppers and advance them over the dies and into engagement with a stop or locating member 27. At this time, the apertures 1% will be aligned with apertures 23 in the die holder 12.

A movable tool holder 3% has a projection 31 connected to a reciprocal ram 32 of the press. The tool holder is supported for vertical movement by guide rods 32, the lower ends of which are fixedly mounted in the base ll), While the upper ends are slidable in bushings 33 fixed to the tool holder 3%. The tool holder has members 35' and 36 separated by a diaphragm 37. The member 36 is provided with cylinder-like apertures 38 aligned with the forming dies 15. Forming tools 39 having piston-like heads 4% movably disposed in the apertures 38 are provided with article forming surfaces 41 cooperating with the surfaces 16 of their respective forming dies 15 to form the articles 17. An element 42;, fixed at 43 to the member 36 of the tool holder, has projections 44 formed to straddle the forming tools 3% beneath the piston-like heads at} to hold the tools against displacement but free from movement in their apertures 38.

Guide pins id mounted on a holder 47 fixed to the member 36 have conical ends and are movable with the forming tools 39 to enter the apertures 13 of the articles, there being a pair of guide pins for each article to serve in locating the articles relative to their dies 15 prior to the forming operations.

The diaphragm 37 is formed of a non-compressible flexible material such as neoprene and serves to close an open portion of a chamber fill formed in the member 35 and covering a sufiiciently large area above the forming tools 39, as illustrated in FIG. 2. The diaphragm is firmly held in place between the members 35 and 36 by a series or" annular grooves 51 and projections 52 when the members are drawn closely together by the plurality of screws 53. The chamber 59 is filled with a noncompressible fluid 5s 8110i. as oil so that the influence of the forming tools 3? through the diaphragm on the oil, results in the distribution of the total force evenly through the piston heads to the forming tools so that uniform forces will be applied to all articles.

Operation Baring each cycle of operation, the unit 21 is operated to feed articles 17 from the hoppers to positions above the dies 15 against the stops or locating element 27. Suitable means, not shown, may be provided for the ejection of the formed articles to clear the way for the next articles to be formed. in the present instance,

there are four pairs of forming tools composed in each instance with a stationary forming tool or die 15 and movable forming tool 39. Either forming tool may be fixed .vhile the other tool of each pair is reciprocated through successive operating cycles.

In the present instance, the lower forming tools or dies are sho's n fixed and the upper forming tools 39 are rcciprocated. Therefore, if the upper forming tools 39 should be mounted at fixed positions in the tool holder 36 with their surfaces 41 fixed in alignment and not movable relative to the tool holder 36 to compensate for varied thicknesses of the articles, undesired results would be obtained if one or more of the articles should -vary in thiel' .ess. However, with the present apparatus, the surfaces 41 of the forming tools 39 initially are aligned and the upper ends of their piston-like heads 49 engage the diaphragm 37. As a result, downw'ard movement of the rain 32, to move the tool holder downwardly through its forming cycle, will cause a predetermined force to be applied through the fluid 55 which is non-compressible, through the diaphragm which is non-compressible but flexible, and to the formin" tools 39.

If one of the articles 17 should be of greater thickness than the other articles preventing its forming tools 39 from moving downwardly as far as the other forming tools, this forming tool will cause the diaphragm 37 to upwardly resulting in a disturbance of the non-compressible fluid and the flowing of this fluid against areas which may be increased in size, namely, the areas of the diaphragm above the other piston-like heads resulting in the movement of these other piston-like heads downwardly, the necessary greater distance to produce uniform displacement of all forming tools 39 to produce like formations of all the articles.

It is to be understood that the above described arrangements are sirnply illustrative of the application of the principles of the invention. Numerous other arrangements may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof.

What is claimed is:

l. A multiple forming apparatus comprising:

a plurality of like forming tools having article forming Cal ends of predetermined contours and opposing heads of like contours,

forming dies having surfaces cooperating with the forming ends of the forming tools to form articles of equal or varied thicknesses,

means to support the forming dies in predetermined spaced positions,

a reciprocable holder for the forming tools having apertures to receive the heads and movably support the forming tools in ali nment with their forming dies,

at flexible but non-compressible diaphragm mounted on the forming tool holder transversely of the apertures and the heads of the forming tools,

a chamber disposed in the forming tool holder on a side of the diaphragm opposite the forming tools Where an opening of the chamber larger in area than the combined areas on the heads of the forming tools is sealed closed by the diaphragm, and

a non-compressible fluid permanently filling the chamher so that during movement of the forming tool holder toward the forming dies the non-compressible fluid and diaphragm will cause application of equal pressures to the forming tools although movements of the forming tools toward their forming dies may be varied by the articles of different thicknesses.

2. A multiple forming apparatus according to claim 1 in which:

an element mounted on the rcciprocable holder has projections to straddle fiat sided portions of the forming tools beneath shoulders thcreof to support the forming tools for relative movement in their apertures against the diaphragm.

References Cited in the file of this patent UNITED STATES PATENTS 

1. A MULTIPLE FORMING APPARATUS COMPRISING: A PLURALITY OF LIKE FORMING TOOLS HAVING ARTICLE FORMING ENDS OF PREDETERMINED CONTOURS AND OPPOSING HEADS OF LIKE CONTOURS, FORMING DIES HAVING SURFACES COOPERATING WITH THE FORMING ENDS OF THE FORMING TOOLS TO FORM ARTICLES OF EQUAL OR VARIED THICKNESSES, MEANS TO SUPPORT THE FORMING DIES IN PREDETERMINED SPACED POSITIONS, A RECIPROCABLE HOLDER FOR THE FORMING TOOLS HAVING APERTURES TO RECEIVE THE HEADS AND MOVABLY SUPPORT THE FORMING TOOLS IN ALIGNMENT WITH THEIR FORMING DIES, A FLEXIBLE BUT NON-COMPRESSIBLE DIAPHRAGM MOUNTED ON THE FORMING TOOL HOLDER TRANSVERSELY OF THE APERTURES AND THE HEADS OF THE FORMING TOOLS, A CHAMBER DISPOSED IN THE FORMING TOOL HOLDER ON A SIDE OF THE DIAPHRAGM OPPOSITE THE FORMING TOOLS WHERE AN OPENING OF THE CHAMBER LARGER IN AREA THAN THE COMBINED AREAS ON THE HEADS OF THE FORMING TOOLS IS SEALED CLOSED BY THE DIAPHRAGM, AND A NON-COMPRESSIBLE FLUID PERMANENTLY FILLING THE CHAMBER SO THAT DURING MOVEMENT OF THE FORMING TOOL HOLDER TOWARD THE FORMING DIES THE NON-COMPRESSIBLE FLUID AND DIAPHRAGM WILL CAUSE APPLICATION OF EQUAL PRESSURES TO THE FORMING TOOLS ALTHOUGH MOVEMENTS OF THE FORMING TOOLS TOWARD THEIR FORMING DIES MAY BE VARIED BY THE ARTICLES OF DIFFERENT THICKNESSES. 